Run-in coatings are used, in particular, when working with what are generally referred to as gap-maintaining systems in compressor and turbine components. In this context, the run-in coatings have the function of maintaining a minimal sealing gap between rotating blading and a housing, as well as between stationary blading and the rotating rotor hubs, and of thereby ensuring stable operating characteristics in the context of a highest possible efficiency. The rotating components of the turbine typically have sealing fins which run in against the run-in coatings or seals in a manner known per se. A honeycomb seal of this kind is described by World Patent Application WO 2004/061340 A1. However, the mentioned running-in process can lead to damage to the run-in coating in such a way that no uniform ablation of the run-in coating, respectively of the seal takes place, but rather that local damage occurs in the form of irregularly shaped and relatively deep sections broken out of the run-in coating.
However, in aircraft engines and gas turbines, a crucial factor influencing the efficiency and reliability of the system is the maintaining of a gap between a rotor and a stator. As operating time increases, a degradation, i.e., an enlargement of the gap between the rotor and the compressor housing, resulting from the mentioned local damage, for example, negatively affects both the efficiency, as well as the surge limit of the compressor.
Under known methods heretofore, such damage to the run-in coating necessitates removing the entire run-in coating and subsequently replacing the same. This disadvantageously entails substantial costs.